In an interview with ABC News, the Duke said he had not yet decided whether to extend his service as a search-and-rescue pilot for another year but admitted it was becoming harder to balance with the demands of being second in line to the throne.

"It’s a really difficult one because I really enjoy my time in the Air Force. And I’d love to continue it," he said. "But the pressures of my other life are building. And fighting them off or balancing the two of them has proven quite difficult," he said.

The Duke's current three-year tour of duty is scheduled to end in mid-2013.

Part of his decision will rest on whether he and the Duchess opt to start a family while he is still in the military, which would offer some measure of shelter from the royal spotlight.

However, he dodged questions in the interview with the American television network when pressed for specifics on the timings of any future heir.

“I’m just very keen to have a family and both Catherine and I are looking forward to having a family in the future," he said, but laughingly insisted he would remain "tight lipped" beyond that.

The Duke also revealed that he wore the distinctive red tunic of the Irish Guards at his wedding because the Queen had insisted on it.

"What I really wanted to wear was the Irish Guards' frock coat," he said. "We had a couple of discussions over this matter but as I learned from growing up you don't mess with your grandmother and what she says goes."

Prince Harry expressed his own desire for children in an interview for the same programme, scheduled to mark the Queen's Diamond Jubilee.

"I’ve longed for kids since I was very, very young," he said. "I’m waiting to find the right person, someone who’s willing to take on the job".

Both princes paid generous tribute to their grandmother, with the Duke saying he marvelled at how the then 25-year-old Princess Elizabeth had ascended to the throne in 1952 "as a woman in a man's world".

Prince Harry said the Royal Family was what "makes Britain, Britain" and credited the Queen with keeping the monarchy relevant over six decades.

"She has managed to get the family to move with the times and I think that's incredibly important. You can't get stuck in an old age situation when everything else is changing," he said.

Prince Harry, a captain in the Army, also said that his view of the Queen had changed now that she was also his Commander-in-Chief.

"Once you’re in the military, she means a lot more to you than just a grandmother," he said. "She is the queen. And then you suddenly, it’s like start realizing, you know, wow, this is quite a big deal. And then you get goose bumps and then the rest of it."